TORONTO -- Nearly a century ago, scientists discovered that light can kill the bacteria that causes tuberculosis.

Since then light therapy has become a treatment for jaundiced babies, to eliminate harmful bacteria from surgical patients and to disinfect hospital rooms.

Now, researchers are building on decades' worth of science on light therapy to determine whether the novel coronavirus could similarly be treated or destroyed through the power of light.

Light therapy became a hot topic late April when U.S. President Donald Trump touted an experimental light probe to treat coronavirus infections in the lungs. At the time, the technology was still in the early stages of development.

But the fact is some scientists say there is merit in studying light therapy as a possible tool against COVID-19.

"I'm all for looking at this technology and seeing what diseases it can be used to benefit patients," said Guillermo Tearney, co-director of the Mass General Brigham Center for COVID Innovation.

"It's a relatively safe technology, it's easy to implement, and so why not try and see if it could be useful to patients who are suffering from COVID."

There are several studies proposed or underway to test various forms of light, using different ways of delivering it into the body for coronavirus infections, including one here in Canada.

Dr. Roy Tingley, a researcher in Nova Scotia, is leading a trial that uses a two-pronged device called a Vielight, which clips onto a patient's nostril and emits red light. The second part goes over the breast bone and emits infrared light.

The plan is to test 280 COVID-19 patients in Ontario and the U.S. to see whether or not it helps them get better faster. Half the participants will receive Vielight treatment and the other half will get standard therapy.

"We presume theoretically that it will actually speed up the recovery and keep patients who might otherwise end up in hospital from having to go to the hospital," Dr. Tingley told CTV News.

The trial will study patients over 30 days and ask them to track their symptoms in a daily survey following twice-a-day treatment with the Vielight. After six months, the data will be reviewed to see if the method helped.

Studies suggest that some forms of light appear to destroy coronaviruses in the lab setting.

Scientists think the light therapy affects cells producing a reaction that allows them to function more normally. In the case of COVID-19, that may help dampen down immune system overreaction that leads to often deadly "cytokine storms."

"So what light therapy can do is activate pathways that would stop cells from dying, which is also useful when you've got something like COVID-19 destroying cells all over the body," says Michael Hamblin, a former associate professor at Harvard Medical School.

It's all still largely theoretical since much of the research for COVID-19 is in the early stages of investigation.

The light therapy touted by Trump is also is still in development. According to a clinical trials website, it is to be tested on five COVID-19 patients on ventilators to see if it will lessen the viral load and disease severity.

A note of caution: no form of light therapy has been proven to work against COVID-19. Some forms of UV light can be harmful and can trigger sunburns and can eventually cause melanoma.